Question

DATE 1. How many moles of Na are there in 47.3 g of Na? 2. Calculate the number of grams of sulfur in 112.4 moles of sulfur. 3. Calculate number of atoms in 4.6 g of calcium. 4. How many H atoms are in 272.5 g of methanol, CH0? 5. For the given reaction N, (g) +3H,(g)->2NH(g) a. How many moles of NH, are formed by the complete reaction of 0.154 moles of H? b. How many grams of NH, is formed by the complete reaction of 1.44g of N? 6. The reaction between aluminum and iron (III) oxide can generate temperatures approaching 3000 C and is used in welding metals: 2 Al FeO AlO, 2 In one process, 24 g o (a) Calculate the mass (in grams) of Al,O, formed. (b) How much excess reagent (in grams) is left at the end of the reaction? (Molar masses of Fe,O, = 159.69 g / mol and ALO, = 101.96 g/mol) 7. For the following reaction: CH, +20, à CO,+ 2HO In one process 1.54 x 10'g of CH, react with 2.00 x 10 g of O (a) Calculate the theoretical yield of H,O (b) Calculate the % yield if 80.3 g of H,O are obtain.

Answer 1

Number of moles = nass molar mass 23 a/m I mole sulfur = 32 g x 32 a woie 3 3 2.3 4-6 g 40.07 3/naole x 6,023 X 10-drms No. of atoms龠 males。f cho = 272.sg -8.s2 mal